1. Field of the Invention
The present invention relates to a composition for forming an electroconductive film such as an electrode or a wiring, a method for forming an electroconductive film such as an electrode or a wiring utilizing such composition, and a method for producing an image forming apparatus utilizing such composition and/or method.
2. Related Background Art
For forming a pattern of an electroconductive film such as an electrode or a wiring on a substrate, there have been known, for example, (1) a method of coating paste, containing an electroconductive material, on a substrate by screen printing method and drying and baking such paste (Japanese Patent Application Laid-Open No. 8-185818 etc.), (2) a transfer method (offset printing method) (Japanese Patent Application Laid-Open No. 8-236017 etc.), (3) a method of coating the entire surface of a substrate with metal-containing solution, then drying and baking such solution to form a metal film, covering a specified area with a mask such as photoresist and removing the metal film by etching in the area not covered by the mask, and (4) a method of adding a photosensitive material to metal-containing paste, then exposing a desired portion to light and executing development thereby forming a pattern of the electroconductive film (Japanese Patent Application Laid-Open Nos. 5-114504 and 8-176177).
However, the above-mentioned method (1) is difficult to apply to a fine pattern, and the method (2) is insufficient in the uniformity and reproducibility of the film thickness. Also the method (3) requires the use of a strong acid for etching particularly in case the pattern is composed of a noble metal such as platinum, and a fine circuit is difficult to form because the resist material is attached or the insulating substrate is eroded. Also the method (4), involving the use of organic solvent, requires an explosion-proof facility for coating, drying and baking steps and extensive care in the handling of the chemicals, and there is involved a significant environmental burden because a large amount of chlorine-containing organic solvent is used also in the development step.
In consideration of the foregoing, the object of the present invention is to enable easy formation of a pattern of an electroconductive film such as a fine electrode, a fine wiring and the like with a composition utilizing aqueous solvent easy to handle and posing little environmental burden.
According to a first aspect of the present invention, a composition for forming an electroconductive film comprising a water-soluble photosensitive resinous component, a water-soluble organometallic compound component capable of forming an electroconductive film by baking, and an aqueous solvent component is provided.
The above-mentioned first aspect includes, as preferred embodiments thereof, that the water content in the aforementioned aqueous solvent component is 70 wt. % or more;
the water content in the aforementioned aqueous solvent component is 90 wt. % or more;
the aforementioned aqueous solvent component is solely composed of water;
the aforementioned organometallic component is a platinum complex;
the aforementioned organometallic component is a metal complex of which ligand is a nitrogen-containing compound having at least a hydroxyl group in the molecule;
the aforementioned nitrogen-containing compound having at least a hydroxyl group in the molecule is a nitrogen-containing compound having eight or less carbon atoms;
the aforementioned photosensitive resinous component is insolubilized in developing liquid by light irradiation; and
the aforementioned photosensitive resinous component is solubilized in developing liquid by light irradiation.
A second aspect of the present invention relates to a method utilizing the aforementioned composition for forming an electroconductive film, such as an electrode or a wiring, of the first aspect employing the photosensitive resinous component of a type insolubilized in the developing liquid by light irradiation. And, the second aspect is to provide a method for forming an electroconductive film comprising a coating step of coating the electroconductive film forming composition on the surface of a substrate, a drying step of drying the coated film of the aforementioned composition, an exposure step of exposing the coated film to a predetermined pattern, a development step of removing the non-exposed portion of the coated film, and a baking step of baking the remaining exposed portion of the coated film.
A third aspect of the present invention relates to a method utilizing the composition of the first invention employing the photosensitive resinous component of a type solubilized in the developing liquid by light irradiation. And, the third aspect is to provide a method for forming an electroconductive film comprising a coating step of coating the composition on the surface of a substrate, a drying step of drying the coated film of the composition, an exposure step of exposing the coated film to a predetermined pattern, a development step of removing the exposed portion of the coated film, and a baking step of baking the remaining non-exposed portion of the coated film.
The above-mentioned second and third aspects include, as preferred embodiments thereof, that the aforementioned coating step is a step executed by a method selected from the spin coating method, immersion coating method, spray coating method, stamp coating method, roller coating method, slit coating method and ink jet coating method;
the aforementioned coating step is a step employing ink jet coating method; and
the aforementioned coating step is a step employing screen printing method, offset printing method or flexo printing method.
A fourth aspect of the present invention is to provide a method for producing an image forming apparatus provided with plural electron emitting devices and an image forming member for forming an image by the irradiation with electron beams emitted from the electron emitting devices, wherein an electrode and/or a wiring to be employed in the aforementioned image forming apparatus is prepared by the method of the second or third aspect.